Review of MFJ-1984MP End-Fed Multi-band Antenna (# 89)

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This turned out to be one weird antenna. It's an end-fed multi-band antenna that's best used in a portable environment. I had to get MFJ's help to figure out what was going on; I provide all this info in the video. This is the summer of antennas! I learn new things every day! (I skipped a number--#88 is coming). Subscribe: / davidcasler . Ask Dave Playlist: goo.gl/inaQeB. Tip Jar: ke0og.net/tip-jar
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8 авг 2017

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Комментарии : 256

@johnwmacdonald994 6 лет назад

Great video, Dave, largely because you're able to give such sound technical interpretation as to what's going on, where I at least would be pretty lost. Thanks as always. -KC1DIW

@ossiemoore941 8 месяцев назад

Thank you for the "stop the press" segment on this. I have been going crazy wondering about 40m on mine. Doing what you did actually helped greatly.

@09keller 5 лет назад

David, I was just looking at this antenna and found your evaluation. It was extremely helpful. Thanks for all that you do for the amateur community. Your knowledge base and professorial style are great! Thanks

@vcl608 Год назад

Dave, thank you for your commitment to helping fellow hams. Your videos are extremely informative and we appreciate you!

@johnmarron1944 2 года назад

I got one from UK Antennas straight out of the box a 49;1 transformer 66ft ish .connected to it .boom no problems an 40 20 15 and 10 so then ordered the 110uH coil added that on the end with about another 8ft of wire and now got 80mtr too no problems at all 😉👍

@DaninVirginia 4 года назад

Hey Dave you've got some hummingbirds showing up for a lesson at 22:00! Great review, appreciate your thoroughness

@TheAx504 4 года назад

I have one on it’s way! Great review and valuable information. Cheers!

@jamesstaley5611 4 года назад

At least your humming bird feeder works :)

@AdamosDad 4 года назад

I was watching them as well, there was a lot of activity at the feeder but not so much on 40. KD9OldAssMan

@N4KRX 6 лет назад

Excellent review! I truly enjoy your videos. Thanks for posting.

@jamesfoley2720 3 года назад

I own one of these and it works VERY well with my FT818ND. This antenna is part of my portable station.

@VlogdeHeer 4 года назад

I have the MFJ1982 and the MFJ1984, both perform very well. I made contacts (phone) with 100watts over 15000km just hanging 5m above the ground.

@eduardogarciamontesdeoca5935 4 года назад

Thanks Dave for this interesting review...

@Horse335 3 года назад

Awesome videos. I do learn a lot form them. thank you!

@thameswater2561 6 лет назад

The World is falling a part :( we can always rely on David Casler. well done at least you will be here to keep us informed.

@chopperboi89 6 лет назад

I got the MFJ 1622, "apartment antenna" (~ $100). In my case, it was completely useless... It might be good for EmComm, but I would want something a little less unwieldy in that scenario... Since then, I've built my own end fed, running from by the 2nd floor window near my rig, and down across my property, it works great with a tuner from 80-10. Now unless you need a vertical, I'd recommend people just learn a little bit, and build their own too.

@DavidVine-DOCVIDPRO 5 лет назад

Thanks for the detailed and excellent instruction.

@macgyver5108 5 лет назад

You just gained MAJOR credibility points with me wearing that shirt! 😎

@surfcrs 4 года назад

A classic

@kenkramer6529 5 лет назад

Just excellent. Very helpful. Well done.

@timothystockman7533 4 года назад

I recently put up an 85 foot end-fed with a 45 foot counterpoise. I have an MFJ-939 tuner at the feed point and about 125 feet of coax back to the shack. It tunes up on all bands 160 - 6. One night when 80m was open I was able to work Europe wth my 100 watt IC-7100.

@ltdees2362 4 года назад

...I'm a simple man, have plenty of trees and cordage to hang my reliable dipole's...your review enforces my philosophy to stay away from gadgets proclaiming to make my life easier...great review and 73's 😎

@dieselstruck 4 года назад

I agree with you in simplicity. I have to say though, this antenna is not up to par as an EFHW antenna goes. I refrained from actually buying this exact model because of the loose solder I saw on this video. I decided to pay twice for the same type of antenna from somewhere else, where it seems they have a higher quality standard, and it works without a hitch. I have worked FT8, SSB, PSK31, etc and I have gotten great QSO's. EFHW are good antennas and don't require all that Dave had to go trough on this video when built in a consistent manner. Also, no counterpoise on these, ground it. TLDR: MFJ makes a crappy EFHW, build your own or buy from a reputable antenna maker and you won't regret it.

@jay-rus4437 3 года назад

Dani El .....running a chameleon emcomm iii, and it is a solid antenna with good performance. I did connect an mfj-915 choke at the tramsformer

@tubetone74 5 лет назад

Very enlightening. Thanks!

@johncliff5417 6 лет назад

Nice review Dave, I was watching with great interest thinking now can Dave prove me wrong here or what. well Dave I have used all kinds of HF antennas to suit the situation of locations that I have had to operate from when in the forces. For the higher frequencies I would usualy pick to use a dipole slung up from trees or tree/mast. For the lower frequencies I would normaly use the trusty wind up drum and plug in unit of a 150 ft, wound up "Dacron" line with embedded tinned copper wire in it. The line was run out for the length required and then trapped into one side between metal washers that were connected to a 5/16 ins plug in terminal, witch was pushed into the antenna base fitted on the side of the vehicle. ie. pull out the whip sections and plug in the wire unit. the far end of the wire could be pulled up into trees or a mast. Whatever losses there were in using a ATU to get a good match was not taken into account. as long has I was able to make contact with the base HQ and pass traffic, usualy by CW was what mattered. On my own back playing with Ferrite torroids winding UNUNs , BALUNS and XFORMERS to try and do what you have just demonstrated, I gave up most of the time and just put it down to experience. Use a doublet or a fan dipole. 73 de John - G0WXU

@mikeharnett2410 6 лет назад

Thanks Dave. I've never had much luck with high impedance antennas, but that was in NM with very high ground mineralization. Here in IL they might work better.

@buckeye5704 5 лет назад

Thanks for the review and the view of your hummers buzzing around the feeder. Going by a couple comments this might work as a temp (and quick up) solution while the house in under construction, possibly longer. Use both feet... HAHAHAHA, I'm stealing that one.

@RicSpivey 3 года назад

First 2 seconds, "I wanna hear his thoughts on this topic" then "awesome shirt!" Then "always great content from Dave!"

@homebrewham2786 3 года назад

love your channel dave keep it going👍📡

@romanhar4151 3 года назад

Thank you very much for this interessting Video. I've learned a lot.

@k5rmj 6 лет назад

Good Video Dave, Thanks

@paulbaker9277 4 года назад

Thank you Dave

@NHSbandUnofficial 6 лет назад

Dave, I built a 9:1 end fed myself. At first I had similar issues. Then with a friend's advice I lowered my transformer to about 2 feet from the ground and connected the ground to my ground rod with no counterpoise . Boom my antenna came alive and works great!

@buckmanaustin3211 5 лет назад

Dan, I just picked up a 1982mp and the downloadable instructions didn't specifically state 2' from the ground, but the illustration pictured it close to the ground as you did, and also said to connect the transformer to a ground rod. Sounds like Dave needs to try that.

@gfl1957 4 года назад

This is a 49:1 end fed half way.

@pd1jdw630 6 лет назад

I later found out ( before I saw this video ) the best swr is conceived by hanging the balun about a meter high of the ground [ =3 feet ]

@scharkalvin 4 года назад

The 80 meter version of this antenna (132' long) would have a harmonic relation on 30 meters, there it's the 3rd harmonic (well close enough for government work). The problem on 40 may have been that the length of the coax was resonant. Perhaps with the box in the air and a LONGER feedline (moving the feedline resonant freq) it might have worked on all bands. Also, you might have needed a choke in the feedline at the rig.

@1903A3shooter 4 года назад

Well one thing you have your transformer box next to a conducting pole that is grounded. I built my first end fed single core matching right off of Steve Ellington,s videos and it was a very good performer on 40. The match was very good, the on air was 2 S-units better than my 40 inverted V at the same above ground. About 40 feet to the center of the V and to the attachment point of the end fed that was a slopping wire to the same point with the transformer 4 feet off the ground at the other end. This only shows that the wire was taking the power and sending it on its way, not every station was this good but to the station near the coast up north from Va. it was doing well. The next one I built is a two core and I have not gotten the same result on 40 with it but it just takes some HAM fiddling. Steve,s videos are very good and he get very good results and had built many. Thanks, Dave E. W4GSM

@322doug 5 лет назад

Dave has the greatest antenna reviews.

@davecasler 5 лет назад

This one was a particularly tough one!

@322doug 5 лет назад

you are very thorough, and fair. very important .@@davecasler

@washingtonstatepicker3460 Год назад

Good review! My efhw from MFJ designed for 160-10 only resonates on 40 and 20!

@zgrafsoftware Год назад

Thanks for the video. Was considering this model, but after watching decided against it. Splendid summary statement at 23:10 -- "This is not a home antenna at all. It's just not!"

@davejones6006 5 месяцев назад

Love the hummingbirds. Just got one of these. Hope I have better luck….

@DonDegidio 6 лет назад

Hi Dave, I was watching the humming birds at the feeder during the Stop Press segment of the video. 73 WB3BJU

@987kestrel 6 лет назад

They were going at it pretty good at 18:05. Oh and also there is a wasp nest under your deck Dave, I'm surprised you did not get stung. Looks like a pretty decent sized one.

@davecasler 6 лет назад

There was also a wasp nest inside the folded umbrella on the picnic table. The wasps love the hummingbird feeders.

@n4lq 6 лет назад

Yes this is an auto transformer but the one's from EU and Myantennas are standard transformers. That's a big difference. The coax will play a role in the antenna therefore I recommend grounding the box right at the earth, going vertical then horizontal in inverted L fashion. That eliminates all the mysterious effects....

@jay-rus4437 3 года назад

Im currently running the emcomm III in an inverted L (kind of a lazy L though). I run 4 counterpoise at 13 feet, the main antenna vertical 22’, then horizontal from there with a slight slope to the end. At the transformer I installed an MFJ-915. Overall my 40 meter performance is pretty good

@francismcclaughry3794 3 года назад

I like these reviews of wire antenna. I have two hundred feet of wire that was used for low wire for like garden lights and I'm thinking of making a home made wire antenna I just watch a bunch of these reviews

@terryjwood 2 года назад

I'm using 75 feet of LMR-400 and I have the box on the ground and the antenna over a tree limb (inverted V). I find get a 1.1: 1 at 7 MHz and 2:1 at 7.3. On 20, 15, and 10 (28-28.5) meters I get about 1.3:1 or better. So far I really like this antenna for my home use! I've worked Chile and Spain on 10 meters and regularly use it on 40 to check into ECARS, SCARS and the Nickle Belt Net from Pittsburgh. Just follow the online instructions and this will work just fine for you!

@sv4rin 4 года назад

Does the fact that your mast supports are metal , interfere with the readings ?

@timothystockman7533 4 года назад

An automatic tuner at the feed point might be the solution for "all band" operation using an end fed antenna.

@kingdick4508 2 года назад

This dude pulls no punches! Great review! 73, de NH7TR…

@Ivor_Barry 2 года назад

If only he had set up the antenna as the manufacturer recommended, it would have worked great for him. It's a great antenna. There's no rocket science behind it. Hams have been using end fed antennas like this one since the 1930s. I've worked all over the world using this antenna with just 100 watts. It's now a permanent fixture at my QTH.

@v4mp1el 3 года назад

@David, do not keep the coax/analyzer in your hands and try not to ly the coax on the ground it will screw up the readings because your are becoming part of the antenna.

@flattire707 3 года назад

David, thanks for the truth about end-feds. There are any number of companies advertising end-fed multi-band antenna claiming no tuner needed. It is just not true.

@RangerUT 2 года назад

I use 1984HP and it work good on 40-10m. 10 is a bit hard to do with no tuner. I have done 300-450watts SSB with really good results. Even barefoot 100w or less I do very good on digital modes. My setup is box is at 8' middle at about 12-13'. end at 28'

@markp.7931 6 лет назад

Hi Dave...I'd love to see a video on antenna switches. Comparing low end (Workman etc) to some higher end models. Thanks...Mark KC1GNH

@thomaswright20 6 лет назад

Hi Dave, I am using the myantennas 80-10 efhw antenna. I have it set up in an inverted L configuration. I have the auto transformer mounted on a wooden 4X4 post on my deck. Directly below that I have an 8 ft. ground rod connected via a 2 ft. ground wire. My swr readings are 2:1 or less on all bands and less than 1.5:1 on most bands. I believe the key to performance is keeping the ground as close as possible to the autotransformer. I also use an ugly balun in line to prevent RF from feeding back into the shack. Hope this helps. Good Luck!

@BadVorlon 6 лет назад

Good choice... I use the same antenna with similar set up, with similar results. Great antenna. 73,

@JayN4GO 6 лет назад

Thomas Wright hey Tom , how does the myantennas 8010 work for you? Do you mind making a video? I have 70 ft between trees but would like to come down and go at a 45 degree right angle to try to get the best I can on 75 meters. Did you have to trim the antenna ?

@dheller777 5 лет назад

Are you having to use a lot of coax or could I keep the coax length under 10 foot as I do with my MFJ end fed?

@DARTHDANSAN Год назад

This is stuff get so confusing?!?!?!? Thanks for share us all the years of experience you have

@johnlomasney 3 года назад

Informative

@BadVorlon 6 лет назад

Dave, I cannot vouch for the MFJ version of this antenna, but I have used another competing version of this antenna (80-10M version) with great success. I have been so impressed with it, it has become my primary base station antenna (yes I live in a dreaded HOA and this is easy to hide). The key to these end-fed antennas using either a 1:49 or 1:64 transformer is the set up. These CAN be set up as a base station antenna. As you found out, these like their feed points close to ground, so they work best as a sloper. I have found if you mount the feed point (and transformer) between 3 and 12 feet above ground, and not use a counterpoise, but rather ground it with a short wire right to a rod (4 foot ground rod in my case) AND feed it with no more than 50 foot of coax... it works great. I have been heard as far away as Australia from the US east coast using it. On most bands 80-10 it needs no tuner (but depends on your terrain). Like you, I have realized this could also be a great field deployable antenna and have built a QRP version based on this design using FT140-43 toroid. 73.

@JosephMassimino 6 лет назад

Great info, I would like to see how you wound the toroid you used for the antenna you made. Did it work well when you tested it? If you can't pot it here, maybe you could send it to me via email from QRZ.

@nojiratzlaff4388 4 года назад

Might want to try using a RigExpert analyzer, Dave. Just a bit more convenient, IME.

@garretthatfield6246 6 лет назад

I have a similar antenna setup in my attic. I was having trouble so I added an “ugly balun” at the feed point and a 30’ counterpoise. The antenna works great on 40-10. K0RGH

@davecasler 6 лет назад

Sound like you've had great results! Thanks for sharing your config.

@larrytruesdellsr.809 3 года назад

What is a ugly balun?

@adlapl 5 лет назад

Do I see humming-birds in the background? They are so wonderful! :)

@davecasler 5 лет назад

Yes, my wife goes through literally gallons and gallons of hummingbird juice. We enjoy them every summer.

@georged8138 Год назад

the best antenna i ever bought

@terryjwood 6 месяцев назад

If I could only have 1 antenna, this would be it! With my MFJ antenna tuner I've been able to use this antenna on 160 m, 80m and 60, 30, 17 and 12 meters too! I've worked 123 countries using 100 watts with this antenna in a little more than a year!

@graywolf1911 6 лет назад

Quite interesting Dave. I have an OCF 265 foot dipole, strung up between trees, it is rated for 160 meters through 2 meters, using a 4:1 Balun at the antenna feed point. The Coax is buried, and is 165 feet of length. I don't think I will be using and endfed anytime soon, but, for some people this may be an acceptable choice.

@davecasler 6 лет назад

The OCFD is a popular antenna, and those I've spoken who have them are quite happy with them. I've never used one myself.

@CodeMasseur 5 лет назад

Hi Dave. I just rewatched this video today -- after having owned the exact same model of MFJ-1984MP end-fed antenna, and I don't use it with a counterpoise, and not only does it work great for me in 10 meter, 15 meter, 17 meter, 20 meter, 30 meter and 40 meter, but I'm actually able to communicate on it with 80 meters as well. I guess YMMV?!? For what it's worth, this antenna goes up almost vertical in the tree, about 40-50 feet up in the air, and the transformer box sits within 2 feet of the ground. 73 de W3DJS in Atlanta, GA, USA.

@scotthawkins9185 5 лет назад

I have had the same good results with this antenna. I have mine installed in an inverted V fashion approximately 70 feet in a tree and the box mounted to a 4x4 post about 5 ft off the ground and 20 feet of coax. Also grounded it at the 4x4 post to copper ground rod. Works excellent so far

@cubeistgames7985 4 года назад

Clearly having that box reasonably close to terra firma matters, and that is how the instructions show it. ( Don’t have one, but this kind of antenna arrangement has some attraction for me.

@warplanner8852 5 лет назад

Dave, thank you for your effort on this review. It tells me to stay a million miles away from this antenna as manufactured by MFJ! Think I will stick with a center fed trap dipole or a trap vertical and keep life simple. 72 de k6whp dit dit

@davecasler 5 лет назад

It's best used as a portable antenna with one end mounted very near the QRP transceiver.

@MarkDecamps 2 года назад

I use it as a POTA antenna with great success.

@symtron 6 лет назад

Really enjoyed the video. Kinda D grade on the antenna, but it is what most antennas are - a comprimise. Thanks and I'll watch more of your posts. I subscribed so I won't miss them when you post. ps - you have interesting hummingbirds, they were flitting in and out of the feed station.

@davecasler 6 лет назад

We're swamped with hummingbirds every year! Too many to count.

@richard-fy2mu 5 лет назад

Out of fairness to MFj redo this keep box 3 to 8 feet up. slope up to 25 feet then down in l. Try with/out counterpoise or ground. Bet it redoes itself and for HOA victims not bad

@JosephAnthonyJosefius 3 года назад

I'm setting up the 800watt version as my permanent QTH HF antenna to replace my G5RV.

@dazzacam9307 5 лет назад

Im running a 9:1 with 88 feet wire ..Box is 32 feet above the ground under my diamond x300 with the wire slopped down and tied off to my back fence ... 80-10 metres through a tuner

@markkerstetter4616 6 лет назад

Doesn't the use diagram (for home use) from the manual show how you ended up? That is, the feed point is very close to the shack (short cable), near the ground (several feet relative to the window in the diagram) and grounded? The diagram shows an inverted-v; your test antenna had two different configurations (horizontal and slanted). Thanks for continuing your great series of videos. You deserve a larger audience and I believe you will get. --Mark, KE8HAA

@davecasler 6 лет назад

Yes, the pictures do illustrate setup. However, they are labeled as examples. There is no text to say that it must be done as in the pictures. I sent MFJ some suggested text to add to their instructions.

@TI3WTI 2 года назад

Did someone noticed that the counterpoise is connected to "noting" inside the box?

@vcl608 Год назад

Thanks!

@davecasler 10 месяцев назад

Many thanks for the generous Super Thanks! 73, Dave, KEØOG

@jiml40 6 лет назад

Sure would like to see you do a review on the MFJ 2389.

@davecasler 6 лет назад

Soooooo many antennas.......soooooooo little time!

@jiml40 6 лет назад

David Casler 😄 I'm sure you can handle it. 😉 There is not a single review on that antenna online anywhere. MFJ will jump at the chance to have it reviewed. Consider it, at least. It's unusual in that it's kinda like a multiple band Hustler, no ground radials, base. Hf through 70 cm , it's like the Maldol hvu-8, , might even be the same manufacturer.

@junkman2758 Год назад

Curious to see the box earth grounded instead of counterpoise

@johnmarshall7212 4 года назад

What do you use for the antenna poles in the test range?

@eddy2561 3 года назад

HI Dave, sorry I'm late to this party......my question, won't an external autotuner such as the MFJ-939i take care of the SWR problem on 40m? It seems you're not a fan of tuners, is this correct? Tnx fer the review, 73 ~ k6sdw

@Scott-K7sce 6 лет назад

dave. next ant be the ultimaxx end fed antennas. i have one and i'm happy with it. my lack of space and keep everyone happy (hoa) it works out great for my situation to be on 10 - 80 meters and be stealthy about it. 73's k7sce

@jimmccusker3155 6 лет назад

I've also been looking at the Ultimaxx and would appreciate a test like this. Thanks for the great video Dave!

@tglenn3121 5 лет назад

Have you ever done any video-reviews of Alpha Delta antennas?

@davecasler 5 лет назад

No, not yet.

@cubeistgames7985 4 года назад

Would the fact that, at 40M the antenna, at 20 ft in the air is a good bit less than the approx. 10M 1/4 wavelength be a factor, maybe?

@Mr_Meowingtons 5 лет назад

i would test it with a 1:1 current choke

@JosephMassimino 6 лет назад

So it appears that the antenna can get all the bands that is says, but not at the same time. What I get from this is that there is no simple way to get low band and high band frequencies to work together on wire antennas. This is because the coax appears to be part of the low band frequencies, but not so much as the frequency increases. I guess that would not surprise anyone. My guess is that if you would put a choke at the balun, and stop RF from flowing back on the coax, you would stop the antenna from working on 40m altogether. Everybody knows that 66 feet is ideal for 40m, so it is the balun that is wrong at that frequency. When 7mhz is put to the wire, the wire is referenced to ground, and that starts at the balun. So i wonder if you were to raise the antenna so the coax going vertical were to match the 66 feet of the antenna before it turned away at the ground. I don't know if you have a way to get that kind of height, but it would be interesting to see what the antenna does. If it works being fully vertical, the next thing might be to test it as a slope. My thought is that the coax would radiate at 7 mhz, but not so much at the higher frequencies. There might have to be a choke as the coax hits the ground ground and makes it turn to the shack. I believe that in a fully vertical configuration the coax that is directly under the wire, will aid 40m, and not bother the higher frequencies as much. If you don't think any of what I suggest would work, I would be interested in the reasons why. I am limited to just wire antennas, so I have been trying to come up with the best I can get. Once a metal roof went on my home, the antenna situation has gotten more complicated.

@tomw5vlt119 4 года назад

A lot of folks I know are using end feds with tuners. Here tho you’re not using a tuner... so I’m not sure the applicability of your methods, or outcomes? Outcomes pertaining to effective multiband solutions ... or not ... or how well?

@IamNewPrepper 5 лет назад

Hi David, A question you may be able to answer. I am not new to radio my first lic was an Advance back in the early 80's. I was with a job that offered no time for radio or other hobbies so within 2 years I sold everything until I was ready to key up again. Now being retired I started up again in March of 2018 and found radio has passed me by. :( I bought a new HF with 4BTV, and 2m/440, FT400 as a base. I decided to buy an MFJ 1984MP to give them a try thinking they have bettered themselves but no surprise they did not. have installed many antennas in my life and really did not care for it once seeing it in hand, I immediately noticed the wire was not going to be heavy enough to support its self. I ran it at about 120 degs leaving enough slack with a relief at the top end to adjust for wind, well up in March fell down in August, the wire broke as I expected (the wire is not strong enough to support its self over the length. Have been trying to contact MFJ but unable to make it past sales and put on hold for upto 27 minutes before I get disconnected. I left my number with sales but no reply. So back to my question, I have the over all footage but I need the lenght from the balun to the chock do you have any ideas on how long?

@davecasler 5 лет назад

I don't have the antenna anymore, so can't measure it. The length might be listed in the manual or on the MFJ webpage for the antenna. Good luck!

@markstimson2633 6 лет назад

Hi dave, i am really needing your help. i woudl like a Baofeng DM-5R. Or a Plus version, i know they say about timeslot problems, but as a RX only unit, can i listen in to repeaters? Thanks in advance

@davecasler 6 лет назад

Yes, they should listen okay. But why not get a unit that actually works at Tier 2? The GD-77 for example.

@dongjuang4196 3 года назад

Hello and thanks for the review. Have you tried to put on the coax near the box a ferrite core?

@davecasler 3 года назад

Unfortunately no, and I gave the antenna away some time ago.

@dongjuang4196 3 года назад

@@davecasler I have ordered myself MFJ-1982MP. It was before I saw your video. Now the antenna is on it's way to me. Shall see what it will be like...

@dongjuang4196 3 года назад

@@davecasler finally I've got it (Ukrainian post is the most incapable in the world). Well I must strongly disagree with you. I've hanged it temporarily: one end right outside my radio shack window at height of 6m above the ground and another end close to a tree at the 8m height. Taking into account sagging one may say that it's hanging almost horisontally at the 6m height. No counterpoise, no coaxial shield grounding. Just simply 8m of RG58 cable from the rig to the antenna. My rig is right next to the window at the second floor of my house. I must say that on all of the bands (3.5M, 7M, 10.1M, 14M, 18.1M, 21M, 24,9M, 28M) I have SWR not higher than 1.8. Only on 28M band I have good SWR just from 28.2M to 28.9M, all the rest of the bands are covered in full, most of them with SWR below 1.5, and 21M with SWR 1.8 @ 21.000kHz. SWR was measured using Diamond SX-100 and 10W rig output. I have disassembled it to look at the transformer and noticed that the ratio is not 7:1 but 6.5:1 (autotransformer with total 13 turns and 2 turns primary). Maybe that is the secret?

@davecasler 3 года назад

@@dongjuang4196 Glad it's working for you!

@sg39 2 года назад

@David Casler, this is what I’m thinking, that the common mode currents are the issue. Use ferrites or a choke in the coax. I am preparing to explore the 49:1 paradigm and as a vertical or a sloper. My 9:1 unun of several years is mounted 5-feet off the ground, is connected to a close 8-foot driven ground rod, and uses a horizontal wire in NVIS fashion. I dealt with the common mode issue using ferrites to keep RF off the 50-foot run of coax to the shack and the rig. I know this is apples and oranges, but it seems that @Dong Juang has the right idea for the 49:1 product that you reviewed.

@eddiesparks2782 6 лет назад

Hello Dave!, Really enjoy your channel. I just purchased this antenna and am awaiting its arrival. Would the adversity with the 40m band be workable with a tuner? Or would that not be advisable. Unfortunately I had planned on having this for fixed station due to limited space. Thanks for any advice - best regards

@davecasler 6 лет назад

This antenna works best in a portable environment with very short coax between the transmitter and the antennas little tuning box.

@Ivor_Barry 6 месяцев назад

@@davecasler Since the shield of the coax is forming the counterpoise for the antenna, longer would be better. I've had great success with this antenna with a long coax (more than 66 feet) and deployed in an inverted V configuration. With an antenna tuner I've used it on all amateur bands, 160 through 10 meters.

@larryak0z672 2 года назад

My EFHW acts like it is shorted. No noise on receive and high SWR. When I unscrew the shield from the pl259 and only the center is hooked to the so239 I get receive noise. What would cause this? Thanks for this great video!

@johnaguiar5891 Год назад

I have the exact same symptom on my efhw - did you find a solution ?

@patrickkerns2022 2 года назад

Would it recieve on all band?I'm looking for a all band recieve only antenna ?will work both indoor and out.any ideas? Thanks

@terryjwood 6 месяцев назад

It will work fine!

@tonyridlen 6 лет назад

Love this video!!!!! KC9QVE Gas City,Indiana

@grasshopper9313 6 лет назад

You might do a Study of radio waves effects at a safe distant from head ,Hand held safe or not so safe. n2wjs Charlie.

@davecasler 6 лет назад

I touched on that in the video on RF safety that I did for the General and Extra video series. Check out my playlists.

@rossbennett449 6 лет назад

I'm new to this sort of calculation, so please help me if I'm missing something. My understanding here is that the problem on the low band was that there was reflected current washing back so it began working as a radiator and that messed up the behavior of the system. Isn't this the classic example for a common mode choke? Instead of moving to a shorter coax, why not make six or eight turns of that coax just below the matching transformer? Again, this is in addition to a good ground at the matching box. Thanks from Ross @ KI5SR

@davecasler 6 лет назад

You're right in general, but in this case the impedance at the feedpoint is very high (thousand or more ohms) so it would have to be a huge choke to create that kind of impedance. So it looks like the match box needs to be relatively close to ground.

@markanderson8066 6 лет назад

the ugly unun aka common mode choke (its NOT a balun) would be on the coax side - where the impedance is 50 ohms.. right? but the typical reason to NOT do that is that the end fed needs a counterpoise which is usually just the coax run. If you do the chock then you probably need the counterpoise. There are other videos on this tho I don't recall the presenters.

@petitebatarddemorte 6 лет назад

What happens when you ground the box? AF5WO TOM

@debohannan4315 5 лет назад

Hi Dave. Since the coax is unbalanced and the antenna is balanced Shouldn't the zip have a choke on it? Seams like the shield of the coax is still radiating .

@davecasler 5 лет назад

It probably is. But while a dipole is inherently balanced when center fed, end feeding is another story. The little balun helps, but needs a counterpoise.

@Scraws 5 лет назад

I have the exact same antenna. Out of the box, each end up about 12ft, and center running through a tree, maybe 20+ ft up, I gat almost all of 40, all of 20 and 15, and CW Data portion of 10. It's a little long, and if I trim it a bit, I think I can fix 10 and 40. Here are my results. MFJ-1994MP Results SWR 2:1 or less: 10M - CW/Data Only. 28.0-28.5 Tuned Low at 28.02 -- 15M Full Band. Tuned at 20.7 -- 20M Full Band. Tuned low at 13.56 -- 30M No Match 4:1 -- 40M Almost 7.0 - 7.25 But Tuned Low. I think if I shorten it a hair, I'll fix 10 & 40

@davecasler 5 лет назад

I'm glad to hear the antenna is working well for you.

@Scraws 5 лет назад

Weird thing. If I remove it from the tree, and have it all in open air, I almost lose 10M. It goes super narrow. 28.5-28.7 is all that's better than 2:1. Weird. I wish I understood this stuff as good as you. 73.

@TridentMissileTech 4 года назад

I have same antenna. It is rigged as a sloper. The box is about 4 feet. I use no counterpoise. It works for 40,20 and 10 without tuner. I Have not tried 30m. I’m using QRP so I am not concerned about a counterpoise. But next time I put it up, I will try a counterpoise

@johninjersey 5 лет назад

I can't help but laugh at the idea of pulling on the coax to adjust the SWR. I can just seeing operating a rig like that. I wonder... what if you stand in mud while pulling on the coax Dave? You could be a good counterpoise that way :) If that doesn't help try standing on your head, in the mud, while pulling the coax with your feet. Not the ideal operating position but a ham has to do what a ham has to do :)

@SteelWolf13 3 года назад

18:50 + This my friends is how you ACTUALLY fish for Radio Signals.

@Stevenfclark 6 лет назад

Dave do you feel the mfj-1982mp would perform any differently, I recently purchased it and plan to mount the box to the second story 20’ of my three story home and feed the connection point through the third story window 30’ and hang the end as high as possible in the trees ideally 60’ or more. I will run a ground wire from the box to a copper ground rod below the 20’ connection, I appreciate your thoughts and consideration 73 Steve KC1HYM

@davecasler 6 лет назад

I had a hard time testing the antenna because my test configuration was different from what MFJ had in mind. We had some back and forth about it. It seems the antenna works well in a portable situation with the cable to the radio short and both the near and far ends pretty low and the middle up higher. I would not recommend the antenna for a fixed installation.

@Stevenfclark 6 лет назад

David Casler thank you for the response Dave, I have the 300w 132’ length antenna version and will be trying it in a fixed incline installation...wish me luck, I’ll share my results with you 73 KC1HYM

@cplpinker 4 года назад

Kinda off topic but at 20nm:35 you have humming Birds Photo Bombing. At the feeder. Ha!!

@dave10524 6 лет назад

As a SWL this might be an OK antenna but for transmitting I could see it being a real PIA.

@davecasler 6 лет назад

As a SWL you want something more broadband, meaning lower Q. Generally a simple longwire will do that.

@kevinshieldsw1kps785 5 лет назад

If it’s on the ground how do you keep water out of it? Or snow for that matter? Would you, could you put in waterproof case? New ham here, so new license not it database yet, but trying to absorb. Thanks Dave, wish you lived closer to me! -73- Kevin

@davecasler 5 лет назад

This particular antenna seems suited best for portable use. I suspect mostly with good weather.

@dougtaylor7724 3 года назад

That is a POTA/SOTA single band antenna for sure. Can you imagine someone in a 5th floor apartment trying to tune this?

@terryjwood 2 года назад

That would be a really big apartment! (66 feet!)

@stevenlawhon3695 5 лет назад

Dave i saw another video(qrp) and it was grounded to a 2meter rod. Different model antenna

@stevenlawhon3695 5 лет назад

HyEndFed Mark III VE3BF from Ontario made the vid.

@jeromegrzelak8236 6 лет назад

YOUsaved me alot of money

@mumi009 6 лет назад

I have been using a HWEF multiband antenna from the Dutch company Hyendfed (www.hyendfed.nl). My swr measurements have all been consistent with the manufacturer's specs (configured as sloper using a 12 meter spiderbeam telescope mast, matchbox 3 meters above ground. No tuner, ground, or counterpoise required. I have used this portable and as a home station antenna with 50 meters of coax. I have the 10 to 80 meter, 200w pep version. The 80 meter stub can be easily adjusted for optimal swr All in all, this has been the best store bought wire antenna I own. David DM3BC

@dheller777 5 лет назад

I have the MFJ with the same problems on 40 meters as Dave. Mine is a sloper with the box about 8 foot off the ground mounted on my 2 meter antenna pole. I have great swr on 10-15 and 20 but can't get lower than 2-1 on 40 even with my antenna tuner. Does the Hyendfed model require a long length of coax or could I still use the 10 foot length I now have on my MFJ?